Unhealthy alcohol use (i.e. the spectrum ranging from heavy drinking that risks health consequences to dependence) is common among HIV-infected persons and is associated with worse health outcomes among people with HIV infection. However, much remains unknown about alcohol-related health effects in those affected by multiple drugs (particularly opioids), or about specific health effects such as detriment to bone. Alcohol use can disrupt bone remodeling by suppressing formation and increasing resorption; heavy alcohol use is associated with both osteopenia (low bone mineral density [BMD]) and incidence of fractures. Osteopenia is common among HIV-infected patients, and fractures are more common in these patients than among adults without HIV infection. Duration of HIV infection has been found to be associated with low BMD, and antiretroviral therapy (ART) also appears to be associated with BMD decline. While bone health is likely affected by HIV infection, ART, alcohol and other drug (e.g. opioid) use (in addition to other known risk factors), the alcohol-osteopenia association among those with HIV infection is not well-characterized. It is not known whether there is an association, the magnitude and nature of that association, and how the relationship is affected by other commonly co-occurring factors (e.g. opioid use, ART).